Even late preterm birth can be detrimental

Preterm birth-even late preterm-increases the chances that the child will be prescribed medication for attention-deficit/hyperactivity disorder (ADHD) later in life, according to the results of a study from Sweden.

Researchers gathered and analyzed data from a Swedish database on more than 1 million children ages 6 to 19 years; 7,506 of them had taken ADHD drugs. The most commonly purchased was methylphenidate (87.8%), followed by atomoxetine (9.2%), and amphetamine (3%).

The researchers found step-wise increases in odds ratios for having taken ADHD medication with increasing degree of prematurity at birth. Compared with infants born at 39 to 41 weeks' gestation, those born at 23 to 28 weeks had the highest risk for subsequently taking ADHD drugs with an odds ratio [OR] of 2.1 (1.4-2.7); 15 of every 1,000 babies born between 23 and 28 weeks went on to take ADHD drugs during school years compared with 6 of 1,000 born full-term.

The researchers also found that social adversity, as expressed by low maternal education, modifies the risk for ADHD in moderately preterm birth. They emphasized that their study gathered data on children prescribed ADHD drugs, not those diagnosed with the disorder.

Lindström K, Lindblad F, Hjern A. Preterm birth and attention-deficit/hyperactivity disorder in schoolchildren. Pediatrics. 2011;127(5):858-865.